Polymers of carbon monoxide and olefins, such as ethylene, have been known and available in limited quantities for many years. For example polyketones are disclosed in Kirk-Othmer Encyclopedia of Chemical Technology, Second Edition, Vol. 12, p. 132, 1967, and in Encyclopedia of Polymer Science and Technology, 1968, Vol. 9, 397-402. Kirk-Othmer Encyclopedia of Chemical Technology notes that utilities for polyketones include the use of polyketones alone or as additives in waxes and surface coating applications. The low molecular weight copolymers in particular may be used as intermediates for the production of plastics, as components in blends with other polymers (such as waxes and greases) and as pour-point depressants for middle distillate petroleum fuel products. See, for example, U.S. Pat. Nos. 2,495,285, 2,577,208 and 2,641,590 and Canadian Pat. No. 834073, which disclose utility and use for low molecular weight polyketones. The higher molecular weight polymers have use and utility as disclosed in U.S. Pat. Nos. 2,495,286 and 4,076,911 as premium thermoplastics for fibers, films, injection molding, compressing molding or blowing applications.
It is known that polyketones may be prepared by contacting CO and ethylene monomers in the presence of a catalyst. High molecular weight polymers of ethylene which contain small quantities of carbon monoxide can be prepared with the aid of Ziegler catalysts. Low molecular weight polymers of carbon monoxide with ethylene and possibly other olefinically unsaturated hydrocarbons in which all monomer units occur distributed at random within the polymer can be prepared with the aid of radical catalysts such as peroxides. A special class of the polymers of carbon monoxide with ethylene is formed by the high molecular weight linear polymers in which the monomer units occur in alternating order and which polymer consist of units with the formula --CO--(C.sub.2 H.sub.4)--. Such polymers can be prepared with the aid of, among others, phosphorus-, arsenic-, antimony-, or cyanogen-containing compounds of palladium, cobalt or nickel as catalysts.
High molecular weight linear polymers of carbon monoxide and ethylene in which monomer units occur in alternating order and which polymers consist of units of the formula ##STR1## can be prepared by using Group VIII metal organic phosphine compounds as a catalyst, such as palladium organic phosphine compounds. For example, U.K. Pat. No. 1,081,304, U.S. Pat. No. 3,689,460, and U.S. Pat. No. 3,694,412 disclose processes using palladium catalysts having monodentate alkyl phosphine ligands. Similar palladium catalysts having monodentate phosphine ligands are disclosed in the articles found in J. Am. Chem Soc. 1982, 104, 3520-2, Organometallics 1984, 3, 866-70, Proc. Ind. Assoc. Cult. Sci. 1985, 68B, 1-5 and CHEMTECH 1986, 1, 48-51. European patent application 121,965 discloses a process for polymerizing CO and alkenically unsaturated hydrocarbon using a Group VIII metal complex having bidentate phosphorous, arsenic or antimony ligands. Application of these catalysts to a monomer mixture which, in addition to carbon monoxide and ethylene, comprises at least one olefinically unsaturated hydrocarbon having the general formula C.sub.x H.sub.y, which hydrocarbon has fewer than 20 carbon atoms and contains an olefinically unsaturated --CH.dbd.CH-- group, leads to the formation of polymers with units of the formula ##STR2## and units of the general formula ##STR3## occurring randomly distributed within the polymer. The structure of the copolymers and "terpolymers" differs only in that in case of the "terpolymers" a unit of ##STR4## is encountered at some random places in the polymer instead of a unit of ##STR5##
These polymers have excellent mechanical properties; especially, very high strength stiffness and impact resistance. However, the use of the Group VIII metal organic phosphine compounds as catalysts has the drawback that they are highly susceptible to oxidation. In the presence of air they are converted into phosphine oxides, which do not possess catalytic activity. Since generally the organic palladium phosphine compounds are very active catalysts, only small amounts are needed to carry out the polymerization. As a consequence, even traces of air will be sufficient for these catalysts to become deactivated. Therefore, complete freedom from air contact should be ensured during transport, storage and use of these catalysts.